Long‐Wavelength Limit of the Structure Factor of Liquid Metals from the Charged Hard‐Sphere Reference System

Abstract

AbstractA detailed study of the long‐wavelength limit S(0) of the structure factor of alkali metals and some polyvalent metals at their freezing points using the charged hard‐sphere reference system is made. In order to investigate the role of refinements in the description of the electron‐ion interaction, use is made of both the Ashcroft empty‐core model (ECM) potential and a non‐local pseudopotential which incorporates high‐order perturbation corrections. The results obtained from the random‐phase approximation (RPA) are compared with those using the mean‐density approximation (MDA). Our calculations indicate that to obtain an accurate description of S(0) within the present framework, a good method of dealing with the electron‐ion pseudopotential is essential. It is also observed that the MDA correction in most cases does not lead to a remarkable improvement on those obtained from the RPA.